<template>
  <div class="login_container">
    <div class="login_box">
      <!-- 头像区 -->
      <div class="avatar_box">
        <img src="../assets/logo.png" alt="#">
      </div>
      <!-- 登录区 -->
      <el-form class="login_form" ref="loginFormRef" :model="loginForm" :rules="loginRules">
        <!-- 用户名 -->
        <el-form-item prop="username">
          <el-input prefix-icon="iconfont icon-user" v-model="loginForm.username"></el-input>
        </el-form-item>
        <!-- 密码 -->
        <el-form-item prop="password">
          <el-input prefix-icon="iconfont icon-3702mima" v-model="loginForm.password" type="password"></el-input>
        </el-form-item>
        <!-- 按钮 -->
        <el-form-item class="btns">
          <el-button type="primary" @click="login">登录</el-button>
          <el-button type="info" @click="resetLoginForm">重置</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>

<script>
export default {
  data () {
    return {
      /* 这是登录表单的数据绑定对象 */
      loginForm: {
        username: 'admin',
        password: '123456'
      },
      /* 表单验证规则 */
      loginRules: {
        username: [
          { required: true, message: '请输入用户名', trigger: 'blur' },
          { min: 2, max: 5, message: '长度2到5个字符', trigger: 'blur' }
        ],
        password: [
          { required: true, message: '请输入密码', trigger: 'blur' },
          { min: 3, max: 12, message: '长度3到12个字符', trigger: 'blur' }
        ]
      }
    }
  },
  methods: {
    /* 点击重置表单 */
    resetLoginForm () {
      /* this 表单对象 */
      this.$refs.loginFormRef.resetFields()
    },
    /* 登录前校验 */
    login () {
      this.$refs.loginFormRef.validate(async (vali) => {
        if (!vali) return
        const { data: res } = await this.$http.post('login', this.loginForm)
        if (res.meta.status !== 200) return this.$message.error('登录失败！')
        this.$message.success('登录成功！')
        /* 1.将登录成功之后的 token，保存到客户端的 sessionStorage中
          项目中除了登录之外的其他api接口，必须在登录之后才能访问
          token只应在当前网站打开期间生效，所有将 token 保存在 sessionStorage中
        2.通过编程式导航跳转到后台主页，路由地址是/home */
        window.sessionStorage.setItem('token', res.data.token)
        this.$router.push('/home')
      })
    }
  }
}
</script>

<style lang="less" scoped>
  .login_container {
    position: relative;
    height: 100%;
    background-color: #2b4b6b;
  }

  .login_box {
    width: 450px;
    height: 300px;
    background-color: #fff;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
  }

  .avatar_box {
    width: 130px;
    height: 130px;
    border: 1px solid #eee;
    border-radius: 50%;
    padding: 10px;
    box-shadow: 0 0 10px #ddd;
    position: absolute;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: #fff;

    img {
      width: 100%;
      height: 100%;
      border-radius: 50%;
      background-color: #eee;
    }
  }
  .login_form {
    position: absolute;
    bottom: 0;
    width: 100%;
    padding: 0 20px;
    box-sizing: border-box;
  }
  .btns {
    float: right;
  }
  .btns button {
    width: 88px;
    padding: 10px 16px;
  }
</style>
